rear driveline safety

[AKlowriderZ71]

Ok, so my truck shuts down at 98 MPH, but it gets there quick. I'm looking into HPTuners or something similar, so I can change that, and other things. Here's my question. At what speed is my rear driveline going to become unsafe? It is the one piece rear driveline, made of aluminum, probably 5 or 6 inch diameter, for the extended cab. I remember reading an article several years ago talking about the driveline's critical speed, and the yoke coming apart, or coming out of the t-case, or something like that.

[SCIV]

Dunno. Mine is 2 piece, and have had it to 132. It's still in there.

[AKlowriderZ71]

I can fix that.....where do you park at night......

[85mudblazin]

Mine is a 1 piece and the truck saw 153 once and 110+ several times and it seems to be fine.

[sprayedenali]

i dont know if its the same driveline or not, but ive had my dads yukon denali up to about 135-140, no problems.

[jake_03]

i have that same drivline and i saw somewhere that this driveshaft will come apart about 130-135.i have my limiter set at 125 and havit had any problems

[hog]

Speed really doesnt mean much, its the driveshaft rpm that is important.

I can got 150mph with 2.73 gears and 35" tires with a stock driveline, then have a custom driveline explode when doing a 100mph run with 5.13 gears and 25" tires.

I'm not arguing with anything in this post, I just wanna point out that the driveshaft rpm is the key indicator, not speed.

I have had my truck to 122mph with 4.10 gears and 28" tires. RPM was 4200rpm in OD, or about 5460 driveshaft rpm.

Guys will pour thousands into a high output engine and run a stock driveshaft without a loop, then cry when the truck throws the shaft onthe dyno and destroys their exhaust.

Dont watch the speedo. watch the tach when in OD.

There is acalculator somewhere that will determibe the critical driveshaft rpm for your particular shaft.

U joint condition and driveline angles have a HUGE impact on driveline safety.

peace
Hog

[AKlowriderZ71]

Speed really doesnt mean much, its the driveshaft rpm that is important.

I can got 150mph with 2.73 gears and 35" tires with a stock driveline, then have a custom driveline explode when doing a 100mph run with 5.13 gears and 25" tires.

I'm not arguing with anything in this post, I just wanna point out that the driveshaft rpm is the key indicator, not speed.

I have had my truck to 122mph with 4.10 gears and 28" tires. RPM was 4200rpm in OD, or about 5460 driveshaft rpm.

Guys will pour thousands into a high output engine and run a stock driveshaft without a loop, then cry when the truck throws the shaft onthe dyno and destroys their exhaust.

Dont watch the speedo. watch the tach when in OD.

There is acalculator somewhere that will determibe the critical driveshaft rpm for your particular shaft.

U joint condition and driveline angles have a HUGE impact on driveline safety.

peace
Hog

This is the info that I'm looking for. My sig says I have 3.73 gears. I don't want to take the shaft past its limits, that gets expensive and dangerous. My driveline angles & u-joints are all in perfect working order. I just want to know how far to push it when I start changing the truck's top speed.